/*
|
* Routines to compress and uncompress tcp packets (for transmission
|
* over low speed serial lines).
|
*
|
* Copyright (c) 1989 Regents of the University of California.
|
* All rights reserved.
|
*
|
* Redistribution and use in source and binary forms are permitted
|
* provided that the above copyright notice and this paragraph are
|
* duplicated in all such forms and that any documentation,
|
* advertising materials, and other materials related to such
|
* distribution and use acknowledge that the software was developed
|
* by the University of California, Berkeley. The name of the
|
* University may not be used to endorse or promote products derived
|
* from this software without specific prior written permission.
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
*
|
* Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
|
* - Initial distribution.
|
*
|
*
|
* modified for KA9Q Internet Software Package by
|
* Katie Stevens (dkstevens@ucdavis.edu)
|
* University of California, Davis
|
* Computing Services
|
* - 01-31-90 initial adaptation (from 1.19)
|
* PPP.05 02-15-90 [ks]
|
* PPP.08 05-02-90 [ks] use PPP protocol field to signal compression
|
* PPP.15 09-90 [ks] improve mbuf handling
|
* PPP.16 11-02 [karn] substantially rewritten to use NOS facilities
|
*
|
* - Feb 1991 Bill_Simpson@um.cc.umich.edu
|
* variable number of conversation slots
|
* allow zero or one slots
|
* separate routines
|
* status display
|
* - Jul 1994 Dmitry Gorodchanin
|
* Fixes for memory leaks.
|
* - Oct 1994 Dmitry Gorodchanin
|
* Modularization.
|
* - Jan 1995 Bjorn Ekwall
|
* Use ip_fast_csum from ip.h
|
* - July 1995 Christos A. Polyzols
|
* Spotted bug in tcp option checking
|
*
|
*
|
* This module is a difficult issue. It's clearly inet code but it's also clearly
|
* driver code belonging close to PPP and SLIP
|
*/
|
|
#include <linux/module.h>
|
#include <linux/slab.h>
|
#include <linux/types.h>
|
#include <linux/string.h>
|
#include <linux/errno.h>
|
#include <linux/kernel.h>
|
#include <net/slhc_vj.h>
|
|
#ifdef CONFIG_INET
|
/* Entire module is for IP only */
|
#include <linux/mm.h>
|
#include <linux/socket.h>
|
#include <linux/sockios.h>
|
#include <linux/termios.h>
|
#include <linux/in.h>
|
#include <linux/fcntl.h>
|
#include <linux/inet.h>
|
#include <linux/netdevice.h>
|
#include <net/ip.h>
|
#include <net/protocol.h>
|
#include <net/icmp.h>
|
#include <net/tcp.h>
|
#include <linux/skbuff.h>
|
#include <net/sock.h>
|
#include <linux/timer.h>
|
#include <linux/uaccess.h>
|
#include <net/checksum.h>
|
#include <asm/unaligned.h>
|
|
static unsigned char *encode(unsigned char *cp, unsigned short n);
|
static long decode(unsigned char **cpp);
|
static unsigned char * put16(unsigned char *cp, unsigned short x);
|
static unsigned short pull16(unsigned char **cpp);
|
|
/* Allocate compression data structure
|
* slots must be in range 0 to 255 (zero meaning no compression)
|
* Returns pointer to structure or ERR_PTR() on error.
|
*/
|
struct slcompress *
|
slhc_init(int rslots, int tslots)
|
{
|
register short i;
|
register struct cstate *ts;
|
struct slcompress *comp;
|
|
if (rslots < 0 || rslots > 255 || tslots < 0 || tslots > 255)
|
return ERR_PTR(-EINVAL);
|
|
comp = kzalloc(sizeof(struct slcompress), GFP_KERNEL);
|
if (! comp)
|
goto out_fail;
|
|
if (rslots > 0) {
|
size_t rsize = rslots * sizeof(struct cstate);
|
comp->rstate = kzalloc(rsize, GFP_KERNEL);
|
if (! comp->rstate)
|
goto out_free;
|
comp->rslot_limit = rslots - 1;
|
}
|
|
if (tslots > 0) {
|
size_t tsize = tslots * sizeof(struct cstate);
|
comp->tstate = kzalloc(tsize, GFP_KERNEL);
|
if (! comp->tstate)
|
goto out_free2;
|
comp->tslot_limit = tslots - 1;
|
}
|
|
comp->xmit_oldest = 0;
|
comp->xmit_current = 255;
|
comp->recv_current = 255;
|
/*
|
* don't accept any packets with implicit index until we get
|
* one with an explicit index. Otherwise the uncompress code
|
* will try to use connection 255, which is almost certainly
|
* out of range
|
*/
|
comp->flags |= SLF_TOSS;
|
|
if ( tslots > 0 ) {
|
ts = comp->tstate;
|
for(i = comp->tslot_limit; i > 0; --i){
|
ts[i].cs_this = i;
|
ts[i].next = &(ts[i - 1]);
|
}
|
ts[0].next = &(ts[comp->tslot_limit]);
|
ts[0].cs_this = 0;
|
}
|
return comp;
|
|
out_free2:
|
kfree(comp->rstate);
|
out_free:
|
kfree(comp);
|
out_fail:
|
return ERR_PTR(-ENOMEM);
|
}
|
|
|
/* Free a compression data structure */
|
void
|
slhc_free(struct slcompress *comp)
|
{
|
if ( IS_ERR_OR_NULL(comp) )
|
return;
|
|
if ( comp->tstate != NULLSLSTATE )
|
kfree( comp->tstate );
|
|
if ( comp->rstate != NULLSLSTATE )
|
kfree( comp->rstate );
|
|
kfree( comp );
|
}
|
|
|
/* Put a short in host order into a char array in network order */
|
static inline unsigned char *
|
put16(unsigned char *cp, unsigned short x)
|
{
|
*cp++ = x >> 8;
|
*cp++ = x;
|
|
return cp;
|
}
|
|
|
/* Encode a number */
|
static unsigned char *
|
encode(unsigned char *cp, unsigned short n)
|
{
|
if(n >= 256 || n == 0){
|
*cp++ = 0;
|
cp = put16(cp,n);
|
} else {
|
*cp++ = n;
|
}
|
return cp;
|
}
|
|
/* Pull a 16-bit integer in host order from buffer in network byte order */
|
static unsigned short
|
pull16(unsigned char **cpp)
|
{
|
short rval;
|
|
rval = *(*cpp)++;
|
rval <<= 8;
|
rval |= *(*cpp)++;
|
return rval;
|
}
|
|
/* Decode a number */
|
static long
|
decode(unsigned char **cpp)
|
{
|
register int x;
|
|
x = *(*cpp)++;
|
if(x == 0){
|
return pull16(cpp) & 0xffff; /* pull16 returns -1 on error */
|
} else {
|
return x & 0xff; /* -1 if PULLCHAR returned error */
|
}
|
}
|
|
/*
|
* icp and isize are the original packet.
|
* ocp is a place to put a copy if necessary.
|
* cpp is initially a pointer to icp. If the copy is used,
|
* change it to ocp.
|
*/
|
|
int
|
slhc_compress(struct slcompress *comp, unsigned char *icp, int isize,
|
unsigned char *ocp, unsigned char **cpp, int compress_cid)
|
{
|
register struct cstate *ocs = &(comp->tstate[comp->xmit_oldest]);
|
register struct cstate *lcs = ocs;
|
register struct cstate *cs = lcs->next;
|
register unsigned long deltaS, deltaA;
|
register short changes = 0;
|
int nlen, hlen;
|
unsigned char new_seq[16];
|
register unsigned char *cp = new_seq;
|
struct iphdr *ip;
|
struct tcphdr *th, *oth;
|
__sum16 csum;
|
|
|
/*
|
* Don't play with runt packets.
|
*/
|
|
if(isize<sizeof(struct iphdr))
|
return isize;
|
|
ip = (struct iphdr *) icp;
|
if (ip->version != 4 || ip->ihl < 5)
|
return isize;
|
|
/* Bail if this packet isn't TCP, or is an IP fragment */
|
if (ip->protocol != IPPROTO_TCP || (ntohs(ip->frag_off) & 0x3fff)) {
|
/* Send as regular IP */
|
if(ip->protocol != IPPROTO_TCP)
|
comp->sls_o_nontcp++;
|
else
|
comp->sls_o_tcp++;
|
return isize;
|
}
|
nlen = ip->ihl * 4;
|
if (isize < nlen + sizeof(*th))
|
return isize;
|
|
th = (struct tcphdr *)(icp + nlen);
|
if (th->doff < sizeof(struct tcphdr) / 4)
|
return isize;
|
hlen = nlen + th->doff * 4;
|
|
/* Bail if the TCP packet isn't `compressible' (i.e., ACK isn't set or
|
* some other control bit is set). Also uncompressible if
|
* it's a runt.
|
*/
|
if(hlen > isize || th->syn || th->fin || th->rst ||
|
! (th->ack)){
|
/* TCP connection stuff; send as regular IP */
|
comp->sls_o_tcp++;
|
return isize;
|
}
|
/*
|
* Packet is compressible -- we're going to send either a
|
* COMPRESSED_TCP or UNCOMPRESSED_TCP packet. Either way,
|
* we need to locate (or create) the connection state.
|
*
|
* States are kept in a circularly linked list with
|
* xmit_oldest pointing to the end of the list. The
|
* list is kept in lru order by moving a state to the
|
* head of the list whenever it is referenced. Since
|
* the list is short and, empirically, the connection
|
* we want is almost always near the front, we locate
|
* states via linear search. If we don't find a state
|
* for the datagram, the oldest state is (re-)used.
|
*/
|
for ( ; ; ) {
|
if( ip->saddr == cs->cs_ip.saddr
|
&& ip->daddr == cs->cs_ip.daddr
|
&& th->source == cs->cs_tcp.source
|
&& th->dest == cs->cs_tcp.dest)
|
goto found;
|
|
/* if current equal oldest, at end of list */
|
if ( cs == ocs )
|
break;
|
lcs = cs;
|
cs = cs->next;
|
comp->sls_o_searches++;
|
}
|
/*
|
* Didn't find it -- re-use oldest cstate. Send an
|
* uncompressed packet that tells the other side what
|
* connection number we're using for this conversation.
|
*
|
* Note that since the state list is circular, the oldest
|
* state points to the newest and we only need to set
|
* xmit_oldest to update the lru linkage.
|
*/
|
comp->sls_o_misses++;
|
comp->xmit_oldest = lcs->cs_this;
|
goto uncompressed;
|
|
found:
|
/*
|
* Found it -- move to the front on the connection list.
|
*/
|
if(lcs == ocs) {
|
/* found at most recently used */
|
} else if (cs == ocs) {
|
/* found at least recently used */
|
comp->xmit_oldest = lcs->cs_this;
|
} else {
|
/* more than 2 elements */
|
lcs->next = cs->next;
|
cs->next = ocs->next;
|
ocs->next = cs;
|
}
|
|
/*
|
* Make sure that only what we expect to change changed.
|
* Check the following:
|
* IP protocol version, header length & type of service.
|
* The "Don't fragment" bit.
|
* The time-to-live field.
|
* The TCP header length.
|
* IP options, if any.
|
* TCP options, if any.
|
* If any of these things are different between the previous &
|
* current datagram, we send the current datagram `uncompressed'.
|
*/
|
oth = &cs->cs_tcp;
|
|
if(ip->version != cs->cs_ip.version || ip->ihl != cs->cs_ip.ihl
|
|| ip->tos != cs->cs_ip.tos
|
|| (ip->frag_off & htons(0x4000)) != (cs->cs_ip.frag_off & htons(0x4000))
|
|| ip->ttl != cs->cs_ip.ttl
|
|| th->doff != cs->cs_tcp.doff
|
|| (ip->ihl > 5 && memcmp(ip+1,cs->cs_ipopt,((ip->ihl)-5)*4) != 0)
|
|| (th->doff > 5 && memcmp(th+1,cs->cs_tcpopt,((th->doff)-5)*4) != 0)){
|
goto uncompressed;
|
}
|
|
/*
|
* Figure out which of the changing fields changed. The
|
* receiver expects changes in the order: urgent, window,
|
* ack, seq (the order minimizes the number of temporaries
|
* needed in this section of code).
|
*/
|
if(th->urg){
|
deltaS = ntohs(th->urg_ptr);
|
cp = encode(cp,deltaS);
|
changes |= NEW_U;
|
} else if(th->urg_ptr != oth->urg_ptr){
|
/* argh! URG not set but urp changed -- a sensible
|
* implementation should never do this but RFC793
|
* doesn't prohibit the change so we have to deal
|
* with it. */
|
goto uncompressed;
|
}
|
if((deltaS = ntohs(th->window) - ntohs(oth->window)) != 0){
|
cp = encode(cp,deltaS);
|
changes |= NEW_W;
|
}
|
if((deltaA = ntohl(th->ack_seq) - ntohl(oth->ack_seq)) != 0L){
|
if(deltaA > 0x0000ffff)
|
goto uncompressed;
|
cp = encode(cp,deltaA);
|
changes |= NEW_A;
|
}
|
if((deltaS = ntohl(th->seq) - ntohl(oth->seq)) != 0L){
|
if(deltaS > 0x0000ffff)
|
goto uncompressed;
|
cp = encode(cp,deltaS);
|
changes |= NEW_S;
|
}
|
|
switch(changes){
|
case 0: /* Nothing changed. If this packet contains data and the
|
* last one didn't, this is probably a data packet following
|
* an ack (normal on an interactive connection) and we send
|
* it compressed. Otherwise it's probably a retransmit,
|
* retransmitted ack or window probe. Send it uncompressed
|
* in case the other side missed the compressed version.
|
*/
|
if(ip->tot_len != cs->cs_ip.tot_len &&
|
ntohs(cs->cs_ip.tot_len) == hlen)
|
break;
|
goto uncompressed;
|
case SPECIAL_I:
|
case SPECIAL_D:
|
/* actual changes match one of our special case encodings --
|
* send packet uncompressed.
|
*/
|
goto uncompressed;
|
case NEW_S|NEW_A:
|
if(deltaS == deltaA &&
|
deltaS == ntohs(cs->cs_ip.tot_len) - hlen){
|
/* special case for echoed terminal traffic */
|
changes = SPECIAL_I;
|
cp = new_seq;
|
}
|
break;
|
case NEW_S:
|
if(deltaS == ntohs(cs->cs_ip.tot_len) - hlen){
|
/* special case for data xfer */
|
changes = SPECIAL_D;
|
cp = new_seq;
|
}
|
break;
|
}
|
deltaS = ntohs(ip->id) - ntohs(cs->cs_ip.id);
|
if(deltaS != 1){
|
cp = encode(cp,deltaS);
|
changes |= NEW_I;
|
}
|
if(th->psh)
|
changes |= TCP_PUSH_BIT;
|
/* Grab the cksum before we overwrite it below. Then update our
|
* state with this packet's header.
|
*/
|
csum = th->check;
|
memcpy(&cs->cs_ip,ip,20);
|
memcpy(&cs->cs_tcp,th,20);
|
/* We want to use the original packet as our compressed packet.
|
* (cp - new_seq) is the number of bytes we need for compressed
|
* sequence numbers. In addition we need one byte for the change
|
* mask, one for the connection id and two for the tcp checksum.
|
* So, (cp - new_seq) + 4 bytes of header are needed.
|
*/
|
deltaS = cp - new_seq;
|
if(compress_cid == 0 || comp->xmit_current != cs->cs_this){
|
cp = ocp;
|
*cpp = ocp;
|
*cp++ = changes | NEW_C;
|
*cp++ = cs->cs_this;
|
comp->xmit_current = cs->cs_this;
|
} else {
|
cp = ocp;
|
*cpp = ocp;
|
*cp++ = changes;
|
}
|
*(__sum16 *)cp = csum;
|
cp += 2;
|
/* deltaS is now the size of the change section of the compressed header */
|
memcpy(cp,new_seq,deltaS); /* Write list of deltas */
|
memcpy(cp+deltaS,icp+hlen,isize-hlen);
|
comp->sls_o_compressed++;
|
ocp[0] |= SL_TYPE_COMPRESSED_TCP;
|
return isize - hlen + deltaS + (cp - ocp);
|
|
/* Update connection state cs & send uncompressed packet (i.e.,
|
* a regular ip/tcp packet but with the 'conversation id' we hope
|
* to use on future compressed packets in the protocol field).
|
*/
|
uncompressed:
|
memcpy(&cs->cs_ip,ip,20);
|
memcpy(&cs->cs_tcp,th,20);
|
if (ip->ihl > 5)
|
memcpy(cs->cs_ipopt, ip+1, ((ip->ihl) - 5) * 4);
|
if (th->doff > 5)
|
memcpy(cs->cs_tcpopt, th+1, ((th->doff) - 5) * 4);
|
comp->xmit_current = cs->cs_this;
|
comp->sls_o_uncompressed++;
|
memcpy(ocp, icp, isize);
|
*cpp = ocp;
|
ocp[9] = cs->cs_this;
|
ocp[0] |= SL_TYPE_UNCOMPRESSED_TCP;
|
return isize;
|
}
|
|
|
int
|
slhc_uncompress(struct slcompress *comp, unsigned char *icp, int isize)
|
{
|
register int changes;
|
long x;
|
register struct tcphdr *thp;
|
register struct iphdr *ip;
|
register struct cstate *cs;
|
int len, hdrlen;
|
unsigned char *cp = icp;
|
|
/* We've got a compressed packet; read the change byte */
|
comp->sls_i_compressed++;
|
if(isize < 3){
|
comp->sls_i_error++;
|
return 0;
|
}
|
changes = *cp++;
|
if(changes & NEW_C){
|
/* Make sure the state index is in range, then grab the state.
|
* If we have a good state index, clear the 'discard' flag.
|
*/
|
x = *cp++; /* Read conn index */
|
if(x < 0 || x > comp->rslot_limit)
|
goto bad;
|
|
/* Check if the cstate is initialized */
|
if (!comp->rstate[x].initialized)
|
goto bad;
|
|
comp->flags &=~ SLF_TOSS;
|
comp->recv_current = x;
|
} else {
|
/* this packet has an implicit state index. If we've
|
* had a line error since the last time we got an
|
* explicit state index, we have to toss the packet. */
|
if(comp->flags & SLF_TOSS){
|
comp->sls_i_tossed++;
|
return 0;
|
}
|
}
|
cs = &comp->rstate[comp->recv_current];
|
thp = &cs->cs_tcp;
|
ip = &cs->cs_ip;
|
|
thp->check = *(__sum16 *)cp;
|
cp += 2;
|
|
thp->psh = (changes & TCP_PUSH_BIT) ? 1 : 0;
|
/*
|
* we can use the same number for the length of the saved header and
|
* the current one, because the packet wouldn't have been sent
|
* as compressed unless the options were the same as the previous one
|
*/
|
|
hdrlen = ip->ihl * 4 + thp->doff * 4;
|
|
switch(changes & SPECIALS_MASK){
|
case SPECIAL_I: /* Echoed terminal traffic */
|
{
|
register short i;
|
i = ntohs(ip->tot_len) - hdrlen;
|
thp->ack_seq = htonl( ntohl(thp->ack_seq) + i);
|
thp->seq = htonl( ntohl(thp->seq) + i);
|
}
|
break;
|
|
case SPECIAL_D: /* Unidirectional data */
|
thp->seq = htonl( ntohl(thp->seq) +
|
ntohs(ip->tot_len) - hdrlen);
|
break;
|
|
default:
|
if(changes & NEW_U){
|
thp->urg = 1;
|
if((x = decode(&cp)) == -1) {
|
goto bad;
|
}
|
thp->urg_ptr = htons(x);
|
} else
|
thp->urg = 0;
|
if(changes & NEW_W){
|
if((x = decode(&cp)) == -1) {
|
goto bad;
|
}
|
thp->window = htons( ntohs(thp->window) + x);
|
}
|
if(changes & NEW_A){
|
if((x = decode(&cp)) == -1) {
|
goto bad;
|
}
|
thp->ack_seq = htonl( ntohl(thp->ack_seq) + x);
|
}
|
if(changes & NEW_S){
|
if((x = decode(&cp)) == -1) {
|
goto bad;
|
}
|
thp->seq = htonl( ntohl(thp->seq) + x);
|
}
|
break;
|
}
|
if(changes & NEW_I){
|
if((x = decode(&cp)) == -1) {
|
goto bad;
|
}
|
ip->id = htons (ntohs (ip->id) + x);
|
} else
|
ip->id = htons (ntohs (ip->id) + 1);
|
|
/*
|
* At this point, cp points to the first byte of data in the
|
* packet. Put the reconstructed TCP and IP headers back on the
|
* packet. Recalculate IP checksum (but not TCP checksum).
|
*/
|
|
len = isize - (cp - icp);
|
if (len < 0)
|
goto bad;
|
len += hdrlen;
|
ip->tot_len = htons(len);
|
ip->check = 0;
|
|
memmove(icp + hdrlen, cp, len - hdrlen);
|
|
cp = icp;
|
memcpy(cp, ip, 20);
|
cp += 20;
|
|
if (ip->ihl > 5) {
|
memcpy(cp, cs->cs_ipopt, (ip->ihl - 5) * 4);
|
cp += (ip->ihl - 5) * 4;
|
}
|
|
put_unaligned(ip_fast_csum(icp, ip->ihl),
|
&((struct iphdr *)icp)->check);
|
|
memcpy(cp, thp, 20);
|
cp += 20;
|
|
if (thp->doff > 5) {
|
memcpy(cp, cs->cs_tcpopt, ((thp->doff) - 5) * 4);
|
cp += ((thp->doff) - 5) * 4;
|
}
|
|
return len;
|
bad:
|
comp->sls_i_error++;
|
return slhc_toss( comp );
|
}
|
|
|
int
|
slhc_remember(struct slcompress *comp, unsigned char *icp, int isize)
|
{
|
register struct cstate *cs;
|
unsigned ihl;
|
|
unsigned char index;
|
|
if(isize < 20) {
|
/* The packet is shorter than a legal IP header */
|
comp->sls_i_runt++;
|
return slhc_toss( comp );
|
}
|
/* Peek at the IP header's IHL field to find its length */
|
ihl = icp[0] & 0xf;
|
if(ihl < 20 / 4){
|
/* The IP header length field is too small */
|
comp->sls_i_runt++;
|
return slhc_toss( comp );
|
}
|
index = icp[9];
|
icp[9] = IPPROTO_TCP;
|
|
if (ip_fast_csum(icp, ihl)) {
|
/* Bad IP header checksum; discard */
|
comp->sls_i_badcheck++;
|
return slhc_toss( comp );
|
}
|
if(index > comp->rslot_limit) {
|
comp->sls_i_error++;
|
return slhc_toss(comp);
|
}
|
|
/* Update local state */
|
cs = &comp->rstate[comp->recv_current = index];
|
comp->flags &=~ SLF_TOSS;
|
memcpy(&cs->cs_ip,icp,20);
|
memcpy(&cs->cs_tcp,icp + ihl*4,20);
|
if (ihl > 5)
|
memcpy(cs->cs_ipopt, icp + sizeof(struct iphdr), (ihl - 5) * 4);
|
if (cs->cs_tcp.doff > 5)
|
memcpy(cs->cs_tcpopt, icp + ihl*4 + sizeof(struct tcphdr), (cs->cs_tcp.doff - 5) * 4);
|
cs->cs_hsize = ihl*2 + cs->cs_tcp.doff*2;
|
cs->initialized = true;
|
/* Put headers back on packet
|
* Neither header checksum is recalculated
|
*/
|
comp->sls_i_uncompressed++;
|
return isize;
|
}
|
|
int
|
slhc_toss(struct slcompress *comp)
|
{
|
if ( comp == NULLSLCOMPR )
|
return 0;
|
|
comp->flags |= SLF_TOSS;
|
return 0;
|
}
|
|
#else /* CONFIG_INET */
|
|
int
|
slhc_toss(struct slcompress *comp)
|
{
|
printk(KERN_DEBUG "Called IP function on non IP-system: slhc_toss");
|
return -EINVAL;
|
}
|
int
|
slhc_uncompress(struct slcompress *comp, unsigned char *icp, int isize)
|
{
|
printk(KERN_DEBUG "Called IP function on non IP-system: slhc_uncompress");
|
return -EINVAL;
|
}
|
int
|
slhc_compress(struct slcompress *comp, unsigned char *icp, int isize,
|
unsigned char *ocp, unsigned char **cpp, int compress_cid)
|
{
|
printk(KERN_DEBUG "Called IP function on non IP-system: slhc_compress");
|
return -EINVAL;
|
}
|
|
int
|
slhc_remember(struct slcompress *comp, unsigned char *icp, int isize)
|
{
|
printk(KERN_DEBUG "Called IP function on non IP-system: slhc_remember");
|
return -EINVAL;
|
}
|
|
void
|
slhc_free(struct slcompress *comp)
|
{
|
printk(KERN_DEBUG "Called IP function on non IP-system: slhc_free");
|
}
|
struct slcompress *
|
slhc_init(int rslots, int tslots)
|
{
|
printk(KERN_DEBUG "Called IP function on non IP-system: slhc_init");
|
return NULL;
|
}
|
|
#endif /* CONFIG_INET */
|
|
/* VJ header compression */
|
EXPORT_SYMBOL(slhc_init);
|
EXPORT_SYMBOL(slhc_free);
|
EXPORT_SYMBOL(slhc_remember);
|
EXPORT_SYMBOL(slhc_compress);
|
EXPORT_SYMBOL(slhc_uncompress);
|
EXPORT_SYMBOL(slhc_toss);
|
|
MODULE_LICENSE("Dual BSD/GPL");
|
